Mutations

Question 1

1.

Point mutation

Answer 1

• Definition: A change in a single base pair of DNA.
  
  • Types:
    
    • Silent Mutation: No change in the protein (due to redundancy in the genetic code).
    • Missense Mutation: Changes one amino acid in the protein, which might affect its function.
    • Nonsense Mutation: A stop codon is introduced, leading to a shortened, nonfunctional protein.

Question 2

2.

Insertion mutation

Answer 2

• Definition: A base pair is added to the DNA sequence.
  
  • Effect: Shifts the reading frame (frameshift), altering all amino acids downstream and usually creating a nonfunctional protein.

Question 3

3.

Deletion

Answer 3

• Definition: A base pair is removed from the DNA sequence.
  
  • Effect: Similar to insertion, it causes a frameshift and often leads to a nonfunctional protein.

Question 4

4.

Frameshift

Answer 4

• Definition: Insertion or deletion of a number of base pairs not divisible by three, shifting the reading frame.
  
  • Effect: Changes the entire amino acid sequence from the mutation onward, usually resulting in a nonfunctional protein.

Question 5

5.

Duplication

Answer 5

• Definition: A section of DNA is copied and inserted into the genome.
  
  • Effect: Can lead to repeated proteins, which might disrupt normal cell functions.

Question 6

6.

Inversion

Answer 6

• Definition: A segment of DNA is reversed within the chromosome.
  
  • Effect: This can disrupt the function of the gene or cause abnormal protein function.

Question 7

7.

Translocation

Answer 7

• Definition: A piece of DNA from one chromosome is transferred to another chromosome.
  
  • Effect: Can disrupt the genes involved or lead to unregulated gene expression, causing diseases like cancer.